This application relates to a contact surface between a dovetail and a rotor slot for a turbine engine fan blade, wherein a compliant layer is disposed along the contact faces.
Gas turbine engines are known, and may include a fan section delivering air to a compressor section. The air is compressed and passed downstream into a combustion section. The air is intermixed with fuel in the combustion section and ignited. Products of this combustion pass downstream over turbine blades which are driven to rotate.
In one type of fan section, a rotor disk is provided with removable fan blades. Typically, the fan blades include an airfoil extending outwardly of the rotor disk and a dovetail which is positioned within a slot in the rotor disk.
During operation, the dovetail is forced into contact with the disk slot. Stresses are created at localized contact areas between the blades and disk slots. Often, the stresses are concentrated near the axial ends of the contact surfaces between the blades and the disk slots. This concentration is undesirable.
It is known to provide a crowned surface on the root of blades to minimize the fillet hoop tensile stresses. The crowned surface can flatten out under load and reduce stress. However, it is not believed that these root designs help reduce the high bearing contact stresses and resulting potential crushing of the axial ends of the roots.